The compressed air is converted into expansion force, to not only replace partial fuel but also reduce the burning and explosion noise.

压缩空气在转化成膨胀力， 替代部分燃料的同时，还能降低燃爆噪声。

youdao

In remarks to reporters, German Defense Minister Franz Joseph Jung suggested that security would be beefed up with the recent deployment of a European Union Rule of Law Mission in Kosovo,or EULEX, and the expansion of Kosovo's own security force in the coming months.

VOA: standard.2009.06.11

We prefer stories with product innovation rather than sales force expansion as a catalyst, but acknowledge its power in relatively under-penetrated markets.

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But exactly what's driving that expansion - the force responsible for pulling the Universe apart, and for want of a better description, dubbed dark energy - remains a mystery.

BBC: Getting the measure of dark energy

The crucial lesson to be learned is that our economic growth depends on a combination of technology change and the expansion of the labor force.

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